Allow all boolean flags to take an optional 'true' or 'false' value

Default is true if no value is specified, so this is fully backwards-compatible.

Closes #8788.

1 files changed, 109 insertions, 45 deletions

diff --git a/src/Text/Pandoc/App/CommandLineOptions.hs b/src/Text/Pandoc/App/CommandLineOptions.hs
index 8c96be58d..2ee304e76 100644
--- a/src/Text/Pandoc/App/CommandLineOptions.hs
+++ b/src/Text/Pandoc/App/CommandLineOptions.hs
@@ -293,18 +293,27 @@ options =
                 ""
 
     , Option "" ["file-scope"]
-                 (NoArg
-                  (\opt -> return opt { optFileScope = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optFileScope = boolValue })
+                  "true|false")
                  "" -- "Parse input files before combining"
 
     , Option "" ["sandbox"]
-                 (NoArg
-                  (\opt -> return opt { optSandbox = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optSandbox = boolValue })
+                  "true|false")
                  ""
 
     , Option "s" ["standalone"]
-                 (NoArg
-                  (\opt -> return opt { optStandalone = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optStandalone = boolValue })
+                  "true|false")
                  "" -- "Include needed header and footer on output"
 
     , Option "" ["template"]
@@ -337,13 +346,19 @@ options =
                  "" -- "Option for wrapping text in output"
 
     , Option "" ["ascii"]
-                 (NoArg
-                  (\opt -> return opt { optAscii = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optAscii = boolValue })
+                  "true|false")
                  ""  -- "Prefer ASCII output"
 
     , Option "" ["toc", "table-of-contents"]
-                (NoArg
-                 (\opt -> return opt { optTableOfContents = True }))
+                (OptArg
+                 (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optTableOfContents = boolValue })
+                 "true|false")
                "" -- "Include table of contents"
 
     , Option "" ["toc-depth"]
@@ -486,8 +501,11 @@ options =
                  "" -- "Length of line in characters"
 
     , Option "p" ["preserve-tabs"]
-                 (NoArg
-                  (\opt -> return opt { optPreserveTabs = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optPreserveTabs = boolValue })
+                  "true|false")
                  "" -- "Preserve tabs instead of converting to spaces"
 
     , Option "" ["tab-stop"]
@@ -529,15 +547,20 @@ options =
                  "" -- "Path of custom reference doc"
 
     , Option "" ["self-contained"]
-                 (NoArg
-                  (\opt -> do
-                    deprecatedOption "--self-contained" "use --embed-resources --standalone"
-                    return opt { optSelfContained = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        deprecatedOption "--self-contained" "use --embed-resources --standalone"
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optSelfContained = boolValue })
+                    "true|false")
                  "" -- "Make slide shows include all the needed js and css (deprecated)"
 
-    , Option "" ["embed-resources"]
-                 (NoArg
-                  (\opt -> return opt { optEmbedResources = True }))
+    , Option "" ["embed-resources"] -- maybe True (\argStr -> argStr == "true") arg
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optEmbedResources =  boolValue })
+                  "true|false")
                  "" -- "Make slide shows include all the needed js and css"
 
     , Option "" ["request-header"]
@@ -550,8 +573,11 @@ options =
                  ""
 
     , Option "" ["no-check-certificate"]
-                (NoArg
-                 (\opt -> return opt { optNoCheckCertificate = True }))
+                (OptArg
+                 (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optNoCheckCertificate = boolValue })
+                 "true|false")
                 "" -- "Disable certificate validation"
 
     , Option "" ["abbreviations"]
@@ -627,13 +653,19 @@ options =
                  "" -- "Accepting or reject MS Word track-changes.""
 
     , Option "" ["strip-comments"]
-                (NoArg
-                 (\opt -> return opt { optStripComments = True }))
+                (OptArg
+                 (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optStripComments = boolValue })
+                 "true|false")
                "" -- "Strip HTML comments"
 
     , Option "" ["reference-links"]
-                 (NoArg
-                  (\opt -> return opt { optReferenceLinks = True } ))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optReferenceLinks = boolValue })
+                  "true|false")
                  "" -- "Use reference links in parsing HTML"
 
     , Option "" ["reference-location"]
@@ -664,19 +696,27 @@ options =
                   ""
 
     , Option "" ["list-tables"]
-                 (NoArg
-                  (\opt -> do
-                    return opt { optListTables = True } ))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optListTables = boolValue })
+                  "true|false")
                  "" -- "Use list tables for RST"
 
     , Option "" ["listings"]
-                 (NoArg
-                  (\opt -> return opt { optListings = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optListings = boolValue })
+                  "true|false")
                  "" -- "Use listings package for LaTeX code blocks"
 
     , Option "i" ["incremental"]
-                 (NoArg
-                  (\opt -> return opt { optIncremental = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optIncremental = boolValue })
+                  "true|false")
                  "" -- "Make list items display incrementally in Slidy/Slideous/S5"
 
     , Option "" ["slide-level"]
@@ -691,14 +731,19 @@ options =
                  "" -- "Force header level for slides"
 
     , Option "" ["section-divs"]
-                 (NoArg
-                  (\opt -> return opt { optSectionDivs = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optSectionDivs = boolValue })
+                  "true|false")
                  "" -- "Put sections in div tags in HTML"
 
     , Option "" ["html-q-tags"]
-                 (NoArg
-                  (\opt ->
-                     return opt { optHtmlQTags = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optHtmlQTags = boolValue })
+                  "true|false")
                  "" -- "Use <q> tags for quotes in HTML"
 
     , Option "" ["email-obfuscation"]
@@ -908,18 +953,27 @@ options =
                  "" -- "Use gladtex for HTML math"
 
     , Option "" ["trace"]
-                 (NoArg
-                  (\opt -> return opt { optTrace = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optTrace = boolValue })
+                  "true|false")
                  "" -- "Turn on diagnostic tracing in readers."
 
     , Option "" ["dump-args"]
-                 (NoArg
-                  (\opt -> return opt { optDumpArgs = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optDumpArgs = boolValue })
+                  "true|false")
                  "" -- "Print output filename and arguments to stdout."
 
     , Option "" ["ignore-args"]
-                 (NoArg
-                  (\opt -> return opt { optIgnoreArgs = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optIgnoreArgs = boolValue })
+                  "true|false")
                  "" -- "Ignore command-line arguments."
 
     , Option "" ["verbose"]
@@ -933,8 +987,11 @@ options =
                  "" -- "Suppress warnings."
 
     , Option "" ["fail-if-warnings"]
-                 (NoArg
-                  (\opt -> return opt { optFailIfWarnings = True }))
+                 (OptArg
+                  (\arg opt -> do
+                        boolValue <- readBoolFromOptArg arg
+                        return opt { optFailIfWarnings = boolValue })
+                  "true|false")
                  "" -- "Exit with error status if there were  warnings."
 
     , Option "" ["log"]
@@ -1098,6 +1155,13 @@ readMetaValue s
   | s == "FALSE" = MetaBool False
   | otherwise    = MetaString $ T.pack s
 
+readBoolFromOptArg ::  Maybe String -> ExceptT OptInfo IO Bool
+readBoolFromOptArg = maybe (return True) readBoolFromArg
+    where readBoolFromArg arg = case toLower <$> arg of
+            "true"  -> return True
+            "false" -> return False
+            _       -> optError $ PandocOptionError "value must be either true or false"
+
 -- On Windows with ghc 8.6+, we need to rewrite paths
 -- beginning with \\ to \\?\UNC\. -- See #5127.
 normalizePath :: FilePath -> FilePath